Port interface for a pneumatic distribution system

ABSTRACT

A port interface for a pneumatic distribution system includes a first flow passage configured to receive fluidized particulate material from an outlet port of a header and to output the fluidized particulate material to an outlet line. The port interface also includes a second flow passage configured to receive a purging airflow and to output the purging airflow to the outlet line. In addition, the port interface includes a knife valve having a blade with a first opening and a second opening. The blade is configured to move between a first position in which the first opening is substantially aligned with the first flow passage and the second opening is substantially aligned with the second flow passage, and a second position in which the first opening is substantially aligned with the second flow passage and a solid portion of the blade is substantially aligned with the first flow passage.

BACKGROUND

The present disclosure relates generally to a port interface for apneumatic distribution system.

Generally, agricultural seeding implements are towed behind a workvehicle, such as a tractor. These seeding implements typically includemultiple row units (e.g., ground engaging opener assemblies) thatexcavate trenches into soil and deposit particulate material, such asseeds and/or fertilizer, into the trenches. In this manner, rows of theparticulate material may be established throughout a field. For example,the particulate material may be stored in a central location, such as ina storage tank of an air cart, and distributed to each of the row unitsfor deposition into the soil. Unfortunately, if a portion of the seedingimplement passes over a region of the field that has already receivedthe particulate material, the region may receive more particulatematerial than desired. As a result, the crop yield within the region maybe reduced and/or particulate material may be wasted, thereby reducingthe efficiency of the seeding process.

BRIEF DESCRIPTION

In one embodiment, a port interface for a pneumatic distribution systemincludes a first flow passage configured to receive fluidizedparticulate material from an outlet port of a header and to output thefluidized particulate material to an outlet line. The port interfacealso includes a second flow passage configured to receive a purgingairflow and to output the purging airflow to the outlet line. Inaddition, the port interface includes a knife valve having a blade witha first opening and a second opening. The blade is configured to movebetween a first position in which the first opening is substantiallyaligned with the first flow passage and the second opening issubstantially aligned with the second flow passage, and a secondposition in which the first opening is substantially aligned with thesecond flow passage and a solid portion of the blade is substantiallyaligned with the first flow passage.

In another embodiment, a port interface for a pneumatic distributionsystem includes a body, and a first flow passage extending through thebody. The first flow passage is configured to receive fluidizedparticulate material from an outlet port of a header and to output thefluidized particulate material to an outlet line. The port interfacealso includes a second flow passage extending through the body. Thesecond flow passage is configured to receive a purging airflow and tooutput the purging airflow to the outlet line. In addition, the portinterface includes a valve at least partially disposed within the body.The valve is configured to facilitate flow of the fluidized particulatematerial through the first flow passage to the outlet line and tofacilitate flow of the purging airflow through the second flow passageto the outlet line while the valve is in a first state, and the valve isconfigured to substantially block flow of the fluidized particulatematerial through the first flow passage to the outlet line and tofacilitate flow of the purging airflow through the second flow passageto the outlet line while the valve is in a second state.

In a further embodiment, a pneumatic distribution system includes aheader having an inlet passage and multiple outlet ports. The inletpassage is configured to receive fluidized particulate material, andeach outlet port is configured to provide the fluidized particulatematerial to a respective outlet line. In addition, the pneumaticdistribution system includes at least one port interface having a firstflow passage with an inlet coupled to a respective outlet port of theheader. The first flow passage is configured to receive the fluidizedparticulate material from the respective outlet port and to output thefluidized particulate material to the respective outlet line. The atleast one port interface also includes a second flow passage configuredto receive a purging airflow and to output the purging airflow to therespective outlet line. In addition, the at least one port interfaceincludes a knife valve having a blade with a first opening and a secondopening. The blade is configured to move between a first position inwhich the first opening is substantially aligned with the first flowpassage and the second opening is substantially aligned with the secondflow passage, and a second position in which the first opening issubstantially aligned with the second flow passage and a solid portionof the blade is substantially aligned with the first flow passage.

DRAWINGS

These and other features, aspects, and advantages of the presentdisclosure will become better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

FIG. 1 is a side view of an embodiment of an agricultural implementcoupled to an air cart;

FIG. 2 is a block diagram of an embodiment of a pneumatic distributionsystem that may be employed within the agricultural implement of FIG. 1;

FIG. 3 is a schematic diagram of an embodiment of a port interface thatmay be employed within the pneumatic distribution system of FIG. 2, inwhich a valve of the port interface is in a first state;

FIG. 4 is a schematic diagram of the port interface of FIG. 3, in whichthe valve is in a second state;

FIG. 5 is an exploded view of an embodiment of a port interface that maybe employed within the pneumatic distribution system of FIG. 2; and

FIG. 6 is a perspective view of the port interface of FIG. 5.

DETAILED DESCRIPTION

Certain agricultural implements (e.g., seeding implements) maydistribute a particulate material (e.g., seeds, fertilizer, etc.) tomultiple row units (e.g., ground engaging opener assemblies).Additionally, each row unit may engage the ground to excavate a trenchinto soil, and each row unit may deposit the particulate material intothe trench. In this manner, rows of the particulate material may beestablished throughout a field. The particulate material may include anysuitable product/material that is desired to be deposited into the soil,such as various types of seeds and fertilizers.

Generally, each row unit does not provide adjustable control over thedeposition of the particulate material. Instead, each row unit mayreceive fluidized particulate material via a respective pneumatic line.In addition, the row unit may enable received particulate material todrop into the trench via gravity. Accordingly, the rate at whichparticulate material is deposited into the soil by each row unit may bebased on fixed parameters, such as the diameter of the pneumatic lineand/or the flow rate of the fluidized particulate material to the rowunit, among other factors.

Generally, the particulate material is stored in a centralized location,such as in a storage tank of an air cart, for distribution to each rowunit. In certain embodiments, the centralized location is pressurized(e.g., via a pneumatic line). In addition, the particulate materialdistribution from the centralized location may be controlled (e.g., viameter roller(s), etc.). Furthermore, it may be desirable to deposit theparticulate material using only a portion of the row units. For example,a region of the soil under the agricultural implement may havepreviously received particulate material, or deposition of theparticulate material within the region may be undesirable (e.g., theregion corresponds to a headland of the field, etc.). In such instances,it may be desirable to control the particulate material flow across theagricultural implement by selectively enabling a portion of the rowunits to deposit the particulate material while disabling anotherportion of the row units.

Accordingly, as will be described in more detail below, a pneumaticdistribution system may include a header having an inlet passage andmultiple outlet ports. The inlet passage is configured to receivefluidized particulate material (e.g., from a storage tank of the aircart, etc.), and each outlet port is configured to provide the fluidizedparticulate material to a respective secondary line. Each secondary linemay be fluidly coupled to a row unit or group of row units (e.g., via asecondary header, tertiary lines, etc.). The pneumatic distributionsystem may also include at least one port interface having a first flowpassage, a second flow passage, and a valve configured to control flowthrough each passage. The first flow passage is configured to receivethe fluidized particulate material from a respective outlet port of theheader and to output the fluidized particulate material to a respectivesecondary line. In addition, the second flow passage is configured toreceive a purging airflow and to output the purging airflow to thesecondary line. The valve is configured to facilitate flow of thefluidized particulate material through the first flow passage to thesecondary line and to facilitate flow of the purging airflow through thesecond flow passage to the secondary line while the valve is in a firststate, and the valve is configured to substantially block flow of thefluidized particulate material through the first flow passage to thesecondary line and to facilitate flow of the purging airflow through thesecond flow passage to the secondary line while the valve is in a secondstate. Accordingly, the at least one port interface may control the flowof the particulate material to the row unit or group of row units thatreceive the particulate material from the respective secondary line. Inaddition, the port interface is configured to flow the purging airflowthrough the respective secondary line and the components (e.g.,secondary header, tertiary lines, row units, etc.) downstream from thesecondary line while the valve is in the first state and the secondstate. The purging airflow may substantially clear the secondary lineand the components (e.g., secondary header, tertiary lines, row units,etc.) downstream from the second line of the particulate material,thereby substantially reducing or eliminating the possibility of thelines/components becoming clogged with the particulate material whileflow through the first passage is substantially blocked. In addition, byutilizing multiple port interfaces (e.g., in which an inlet to the firstflow passage of each port interface is fluidly coupled to a respectiveoutlet port of the header), control of particulate material flow tocertain row units and/or groups of row units that receive theparticulate material from secondary lines fluidly coupled to respectiveport interfaces may be enabled.

FIG. 1 is a side view of an embodiment of an agricultural implement 10coupled to an air cart 12. As depicted, the agricultural implement 10includes a tool frame 14 coupled to a row unit 16 (e.g., ground engagingopener assembly), a header 18, and wheel assemblies 20. The agriculturalimplement may be pulled by a work vehicle (e.g., a tractor) to depositrows of the particulate material. The wheel assemblies 20 may contactthe surface of the soil to enable the agricultural implement 10 to bepulled by the work vehicle. As the agricultural implement 10 is pulled,a row of particulate material may be deposited into the soil by the rowunit 16 (e.g., ground engaging opener assembly). Although only one rowunit 16 is shown, the agricultural implement 10 may include multiple rowunits 16 organized in one or more rows across the agricultural implement10. In some embodiments, the agricultural implement 10 may include oneor more rows of 12, 14, 16, 18, 20, or more row units 16, which may eachdeposit a respective row of particulate material into the soil.

To facilitate depositing the particulate material, each row unit 16(e.g., ground engaging opener assembly), in the illustrated embodiment,includes an opener 17, a press wheel 19, and a particulate material tube21. While the opener 17 engages the soil, the opener 17 may exert aforce onto the soil that excavates a trench into the soil as the rowunit 16 travels through the field. The particulate material may bedeposited into the excavated trench via the particulate material tube21. Then, the press wheel 19 may pack soil onto the depositedparticulate material. In certain embodiments, the press wheel of atleast one row unit may be omitted. For example, at least one press wheelmay be mounted to the frame of the implement behind the at least one rowunit. Furthermore, while the illustrated row unit includes a groundengaging opener assembly, it should be appreciated that in alternativeembodiments, at least one row unit on the implement may include anapplicator assembly configured to deposit particulate material onto thesurface of the field, or any other suitable type of material depositionassembly.

The header 18 may provide the particulate material to the row units 16.In some embodiments, the header 18 may pneumatically distribute theparticulate material from a primary line to secondary lines. Forexample, a primary line 34 may direct particulate material from the aircart 12 (e.g., a metering system 33 of the air cart) to the header 18.Additionally, the header 18 may distribute the particulate material tothe row units 16 via respective secondary lines 22. In certainembodiments, multiple primary lines 34 may direct particulate materialto multiple headers 18. Moreover, multiple secondary lines 22 may extendfrom each header to respective row units 16. Furthermore, in certainembodiments, at least one secondary line may extend to a secondaryheader, and multiple tertiary lines may extend from the secondary headerto respective row units 16.

In the illustrated embodiment, the air cart 12 is towed behind theagricultural implement 10. For example, the agricultural implement 10may be coupled to the work vehicle by a first hitch assembly, and theair cart 12 may be coupled to the agricultural implement 10 by a secondhitch assembly 24. However, in other embodiments, the agriculturalimplement may be towed behind the air cart. In further embodiments, theimplement and the air cart may be part of a single unit that is towedbehind the work vehicle or may be elements of a self-propelled vehicle.

The air cart 12 may centrally store particulate material and distributethe particulate material to the header 18. The air cart 12 includes astorage tank 26, a frame 28, wheels 30, and an air source 32. Asillustrated, the towing hitch 24 is coupled between the tool frame 14and the air cart frame 28, which enables the air cart 12 to be towedwith the agricultural implement 10. Additionally, the storage tank 26 isconfigured to centrally store the particulate material. In someembodiments, the storage tank 26 may include multiple compartments forstoring different types of particulate material. For example, a firstcompartment may store seeds while a second compartment may store a dryfertilizer. In such configurations, the air cart 12 may deliver bothseeds and fertilizer to the implement 10 via separate distributionsystems, or as a mixture through a single distribution system.

From the storage tank 26, the particulate material may be fed into apneumatic metering system 33, which meters the particulate material,fluidizes the particulate material via a fluidizing airflow from the airsource 32, and distributes the particulate material to the header 18 viathe primary line 34. As depicted, the pneumatic metering system 33 ismounted to the bottom of the storage tank 26. To facilitate distributingthe particulate material, the fluidizing air generated by the air source32 is guided though the pneumatic metering system 33 via a plenum 36. Insome embodiments, the air source 32 may be one or more pumps and/orblowers powered by electric or hydraulic motor(s), for example.

In certain embodiments (e.g., embodiments in which the air cart is towedbehind the implement or embodiments in which the air cart is towed infront of the implement), the air source and/or the plenum may be mountedto a rear portion of the air cart (e.g., relative to a direction oftravel). In other embodiments (e.g., embodiments in which the air cartis towed in front of the implement or embodiments in which the air cartis towed behind the implement), the air source and/or the plenum may bemounted to a front portion of the air cart (e.g., relative to thedirection of travel). Furthermore, in embodiments in which the air cartincludes multiple distribution systems, multiple air sources and/orplenums may be utilized. For example, if the air cart includes twoseparate distribution systems for separately distributing seeds andfertilizer to the row units, the air cart may include two air sourcesand two plenums (e.g., one air source and one plenum for eachdistribution system). In embodiments in which the air cart includes asingle distribution system (e.g., in which one or more products aremetered from one or more metering systems into pneumatic lines), asingle air source and/or a single plenum may be utilized. In certainembodiments, multiple air sources and/or multiple plenums may provide anair flow to multiple groups of lines (e.g., one group of lines coupledto each plenum). In such embodiments, corresponding lines from eachgroup may merge in the metering system, thereby establishing a combinedflow to the implement.

In the illustrated embodiment, the primary line 34 is coupled to aninlet passage at a top of the header 18. Accordingly, particulatematerial flows downwardly through the inlet passage to the outlet ports,which are coupled to the secondary lines 22. However, it should beappreciated that in alternative embodiments, the inlet passage may bepositioned at a bottom of the header. Accordingly, particulate materialmay flow upwardly through the inlet passage to the outlet ports.Furthermore, while the header 18 is coupled to the frame 14 of theimplement 10 in the illustrated embodiment, it should be appreciatedthat in alternative embodiments, the header may be coupled to the frameof the air cart or any other suitable location on the system (e.g., thework vehicle, etc.).

FIG. 2 is a block diagram of an embodiment of a pneumatic distributionsystem 38 that may be employed within the agricultural implement ofFIG. 1. As illustrated, the pneumatic distribution system 38 includesthe primary line 34, the header 18 (e.g., primary header), and thesecondary lines 22 (e.g., outlet lines). The primary header 18 isconfigured to receive fluidized particulate material from the primaryline 34 via an inlet passage of the primary header 18. The primaryheader 18 is configured to distribute the fluidized particulate materialto multiple outlet ports 40 of the primary header 18 (e.g.,substantially evenly across the outlet ports 40). While the illustratedprimary header 18 includes four outlet ports 40, it should beappreciated that in alternative embodiments, the primary header mayinclude more or fewer outlet ports (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,or more). Furthermore, in the illustrated embodiment, the outlet ports40 are distributed about the periphery of the primary header 18.However, it should be appreciated that in alternative embodiments, theoutlet ports may be positioned at other portions on the header.

As illustrated, each secondary line 22 is fluidly coupled to arespective outlet port 40. In addition, each secondary line 22 isfluidly coupled to a respective secondary header 42. Each secondaryheader 42 is configured to distribute the fluidized particulate materialfrom a respective secondary line 22 to multiple row units 16 viarespective tertiary lines 44 (e.g., outlet lines). While each secondaryheader 42 is configured to distribute the fluidized particulate materialto three row units 16 in the illustrated embodiment, it should beappreciated that in alternative embodiments, at least one secondaryheader may be configured to distribute the fluidized particulatematerial to more or fewer row units (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9,10, or more). In addition, in certain embodiments, at least onesecondary line may be configured to distribute the fluidized particulatematerial directly to a respective row unit (e.g., without a secondaryheader).

In the illustrated embodiment, the pneumatic distribution system 38includes multiple port interfaces 46. Each port interface 46 is fluidlycoupled to a respective outlet port 40 of the primary header 18, andeach secondary line 22 is fluidly coupled to a respective port interface46. Each port interface 46 is configured to control flow of thefluidized particulate material to a respective secondary header 42. Forexample, in certain embodiments, each port interface 46 may include abody, a first flow passage extending through the body, a second flowpassage extending through the body, and a valve at least partiallydisposed within the body. The first flow passage is configured toreceive the fluidized particulate material from the respective outputport 40 of the primary header 18 and to output the fluidized particulatematerial to the respective secondary line 22. Furthermore, the secondflow passage is configured to receive purging airflow and to output thepurging airflow to the secondary line 22. As used herein, “purgingairflow” refers to an airflow that is substantially free fromparticulate material. For example, the purging airflow may include lessthan 20 percent particulate material by volume, less than 10 percentparticulate material by volume, less than five percent particulatematerial by volume, less than three percent particulate material byvolume, or less than one percent particulate material by volume. Inaddition, the purging airflow may include about zero percent particulatematerial by volume.

The valve is configured to facilitate flow of the fluidized particulatematerial through the first flow passage to the secondary line and tofacilitate flow of the purging airflow through the second flow passageto the secondary line while the valve is in a first state. In addition,the valve is configured to substantially block flow of the fluidizedparticulate material through the first flow passage to the secondaryline and to facilitate flow of the purging airflow through the secondflow passage to the secondary line while the valve is in a second state.Accordingly, each port interface controls the flow of the particulatematerial to the respective secondary header while continuously providingthe purging airflow to the respective secondary header.

By way of example, if the row units associated with one secondary headerare moving toward a region of the field that has already received theparticulate material and/or distribution of the particulate material tothe region is not desired (e.g., the region corresponds to a headland ofthe field, etc.), the valve of the corresponding port interface may betransitioned to the second state, thereby blocking the flow ofparticulate material. For example, a controller may instruct the valveto transition to the second state in advance of the row units reachingthe region, such that flow of the particulate material from the rowunits terminates as the row units enter the region. Furthermore, withthe valve in the second state, the purging airflow continues to drivethe particulate material to exit the row units after the flow ofparticulate material is terminated. As a result, the particulatematerial within the secondary line, the secondary header, the tertiarylines, and the row units is substantially cleared. The purging airflowmay also facilitate the flow of the fluidized particulate materialthrough the secondary line, the secondary header, the tertiary lines,and the row units while the valve is in the first state and particulatematerial is flowing to the row units.

While a port interface is fluidly coupled to each respective outlet portof the primary header in the illustrated embodiment, it should beappreciated that in alternative embodiments, at least one of the portinterfaces may be omitted, such that the secondary header is fluidlycoupled directly to the outlet port of the primary header by thesecondary line. In addition, it should be appreciated that inalternative embodiments, port interface(s) configured to control theflow of the particulate material, while maintaining the flow of thepurging airflow, may be fluidly coupled to one or more outlet ports ofone or more secondary headers. For example, in certain embodiments, portinterface(s) may only be fluidly coupled to outlet port(s) of theprimary header, port interface(s) may only be fluidly coupled to outletport(s) of the secondary header(s), or port interfaces may be fluidlycoupled to outlet port(s) of the primary header and at least onesecondary header.

FIG. 3 is a schematic diagram of an embodiment of a port interface 46that may be employed within the pneumatic distribution system of FIG. 2,in which a valve of the port interface is in a first state. Aspreviously discussed, the header 18 is configured to receive thefluidized particulate material 48 from the primary line via an inletpassage 50 of the header 18. In the illustrated embodiment, the inletpassage 50 extends downwardly to a body 52 of the header 18, and theoutlet ports 40 extend outwardly from/through the body 52. However, itshould be appreciated that in alternative embodiments, the inlet passageand/or the outlet ports may be arranged in a different configuration.For example, in certain embodiments, the inlet passage may extendupwardly to the body of the header, and the outlet ports may extendoutwardly from/through the body.

In the illustrated embodiment, the port interface 46 includes a firstflow passage 54 configured to receive the fluidized particulate material48 from a respective outlet port 40 of the header 18 and to output thefluidized particulate material to a respective secondary line 22. Inaddition, the port interface 46 includes a second flow passage 56configured to receive the purging airflow 58 and to output the purgingairflow 58 to the secondary line 22. The port interface 46 also includesa knife valve 60 (e.g., knife valve assembly) having a blade 62. Theblade 62 includes a first opening 64, a second opening 66, and a solidportion 68. As illustrated, the blade 62 is in a first position in whichthe first opening 64 is substantially aligned with the first flowpassage 54 and the second opening 66 is substantially aligned with thesecond flow passage 56, thereby establishing the first state of theknife valve 60. With the knife valve 60 in the first state, the portinterface facilitates flow of the particulate material to the secondaryline, and the port interface facilitates flow of the purging airflow tothe secondary line.

As discussed in detail below, the blade 62 is configured to move to asecond position in which the first opening 64 is substantially alignedwith the second flow passage 56 and the solid portion 68 issubstantially aligned with the first flow passage 54, therebyestablishing the second state of the knife valve 60. With the knifevalve 60 in the second state, the port interface substantially blocksflow of the particulate material to the secondary line, and the portinterface facilitates flow of the purging airflow to the secondary line.With the flow of particulate material substantially blocked, the purgingair substantially clears the secondary line and the components (e.g.,secondary header, tertiary lines, row units, etc.) downstream from thesecondary line, thereby substantially reducing or eliminating thepossibility of the lines/components becoming clogged with particulatematerial.

In the illustrated embodiment, an inlet port 70 of the first flowpassage 54 is coupled to the respective outlet port 40 of the primaryheader 18. However, it should be appreciated that in alternativeembodiments, the port interface may be positioned remote from theprimary header, and the inlet port of the first flow passage may befluidly coupled to the outlet port of the header via a pneumatic line,for example. Furthermore, in certain embodiments, the purging airflowmay be provided to the second flow passage by the air source (e.g.,blower(s), etc.) that provides the airflow for fluidizing theparticulate material. For example, in the illustrated embodiment, thesecond flow passage 56 is fluidly coupled to the inlet passage 50 of theprimary header 18. Accordingly, the second flow passage 56 may receivethe purging airflow 58 from the inlet passage 50. In certainembodiments, a screen may be positioned at an inlet to the second flowpassage, thereby substantially blocking the flow of particulate materialand facilitating the airflow into the second flow passage. In furtherembodiments, the inlet to the second flow passage may be fluidly coupledto the inlet passage of the header at a bend (e.g., at an inner radiusof the bend), such that a substantial portion of the particulatematerial bypasses the inlet to the second flow passage, and air flowsinto the second flow passage.

In the illustrated embodiment, the knife valve 60 (e.g., knife valveassembly) includes an actuator 72 configured to drive the blade 62between the first and second positions. The actuator 72 is coupled to abody 74 of the port interface 46 by a frame 76. In the illustratedembodiment, the actuator 72 includes a hydraulic cylinder. However, itshould be appreciated that in alternative embodiments, the actuator mayinclude a pneumatic cylinder, an electromechanical actuator, or anyother suitable type of actuator. While the port interface includes aknife valve in the illustrated embodiment, it should be appreciated thatin alternative embodiments, the valve may include any other suitabletype of valve configured to control the flow of the particulate materialthrough the first flow passage while maintaining the flow of purging airthrough the second flow passage. For example, the valve may include arotary valve at least partially disposed within the body of the portinterface, a shutter valve at least partially disposed within the bodyof the port interface, or any other suitable type of valve.

FIG. 4 is a schematic diagram of the port interface 46 of FIG. 3, inwhich the valve 60 is in the second state. With the valve 60 in thesecond state, the blade 62 is in a second position in which the firstopening 64 is substantially aligned with the second flow passage 56, andthe solid portion 68 is substantially aligned with the first flowpassage 54. The solid portion 68 of the blade 62 substantially blocksflow of the particulate material 48 to the secondary line 22, and thefirst opening 64 facilitates flow of the purging airflow 58 to thesecondary line 22. With the flow of particulate material substantiallyblocked, the purging airflow substantially clears the secondary line andthe components (e.g., secondary header, tertiary lines, row units, etc.)downstream from the second line, thereby substantially reducing oreliminating the possibility of the lines/components becoming cloggedwith particulate material.

FIG. 5 is an exploded view of an embodiment of a port interface 46 thatmay be employed within the pneumatic distribution system of FIG. 2. Inthe illustrated embodiment, the first flow passage 54 extends throughthe body 74, and the second flow passage 56 extends through the body 74.Accordingly, both flow passages are at least partially disposed within acommon housing (e.g., body), such that both flow passages are proximateto (e.g., not remote from) one another. As previously discussed, thefirst flow passage 54 is configured to receive the fluidized particulatematerial from an outlet port of the header (e.g., the primary header)and to output the fluidized particulate material to the secondary line.For example, the inlet port 70 of the first flow passage 54 may becoupled to the outlet port of the header. In addition, the second flowpassage 56 is configured to receive the purging airflow (e.g., from theinlet passage of the header) and to output the purging airflow to thesecondary line. For example, the second flow passage 56 may be fluidlycoupled to the inlet passage of the header.

In the illustrated embodiment, the valve 60 (e.g., valve assembly) ispartially disposed within the body 74. For example, the movable blade 62of the valve 60 is configured to be disposed within a slot 78 of thebody 74. The movable blade 62 includes the first opening 64, the secondopening 66, and the solid portion 68. While the valve 60 is in the firststate, the blade 62 is in the first position, such that the firstopening 64 is substantially aligned with the first flow passage 54, andthe second opening 66 is substantially aligned with the second flowpassage 56. Accordingly, with the valve 60 in the first state, the portinterface 46 facilitates flow of the fluidized particulate materialthrough the first flow passage 54 to the secondary line and facilitatesflow of the purging airflow through the second flow passage 56 to thesecondary line. In addition, while the valve 60 is in the second state,the blade 62 is in the second position, such that the first opening 64is substantially aligned with the second flow passage 56, and the solidportion 68 of the blade 62 is substantially aligned with the first flowpassage 54. Accordingly, with the valve 60 in the second state, the portinterface 46 substantially blocks flow of the fluidized particulatematerial through the first flow passage 54 to the secondary line andfacilitates flow of the purging airflow through the second flow passage56 to the secondary line.

FIG. 6 is a perspective view of the port interface 46 of FIG. 5. In theillustrated embodiment, the port interface 46 includes a combiner 80disposed downstream from the valve 60 and configured to combine thefluidized particulate material and the purging airflow. As illustrated,the combiner 80 includes a first inlet 82 fluidly coupled (e.g.,directly coupled) to the first flow passage, a second inlet 84 fluidlycoupled (e.g., directly coupled) to the second flow passage, and anoutlet configured to fluidly couple to the secondary line. While thevalve 60 is in the first state, the combiner 80 combines the flow offluidized particulate material from the first flow passage with thepurging airflow from the second flow passage to establish a combinedflow through the secondary line. Furthermore, while the valve 60 is inthe second state, the combiner 80 directs the purging airflow from thesecond flow passage to the secondary line, thereby enabling the purgingairflow to substantially clear the secondary line and the components(e.g., secondary header, tertiary lines, row units, etc.) downstreamfrom the secondary line. As a result, the possibility of thelines/components becoming clogged with particulate material issubstantially reduced or eliminated.

While only certain features have been illustrated and described herein,many modifications and changes will occur to those skilled in the art.It is, therefore, to be understood that the appended claims are intendedto cover all such modifications and changes as fall within the truespirit of the disclosure.

The invention claimed is:
 1. A port interface for a pneumaticdistribution system, comprising: a first flow passage configured toreceive fluidized particulate material from an outlet port of a headerand to output the fluidized particulate material to an outlet line; asecond flow passage configured to receive a purging airflow and tooutput the purging airflow to the outlet line; and a knife valve havinga blade, wherein the blade has a first opening and a second opening;wherein the blade is configured to move between a first position inwhich the first opening is substantially aligned with the first flowpassage and the second opening is substantially aligned with the secondflow passage, and a second position in which the first opening issubstantially aligned with the second flow passage and a solid portionof the blade is substantially aligned with the first flow passage. 2.The port interface of claim 1, wherein an inlet of the first flowpassage is coupled to the outlet port of the header.
 3. The portinterface of claim 1, wherein the knife valve comprises an actuatorconfigured to drive the blade between the first and second positions. 4.The port interface of claim 3, comprising a frame configured to supportthe actuator on a body of the port interface.
 5. The port interface ofclaim 3, wherein the actuator comprises a hydraulic cylinder.
 6. Theport interface of claim 1, comprising a combiner disposed downstreamfrom the knife valve and configured to combine the fluidized particulatematerial and the purging airflow.
 7. The port interface of claim 6,wherein the combiner comprises a first inlet fluidly coupled to thefirst flow passage, a second inlet fluidly coupled to the second flowpassage, and an outlet configured to fluidly couple to the outlet line.8. The port interface of claim 1, wherein the second flow passage isfluidly coupled to an inlet passage of the header.
 9. A port interfacefor a pneumatic distribution system, comprising: a body; a first flowpassage extending through the body, wherein the first flow passage isconfigured to receive fluidized particulate material from an outlet portof a header and to output the fluidized particulate material to anoutlet line; a second flow passage extending through the body, whereinthe second flow passage is configured to receive a purging airflow andto output the purging airflow to the outlet line, and the purgingairflow is substantially free from the fluidized particulate material;and a valve at least partially disposed within the body, wherein thevalve is configured to facilitate flow of the fluidized particulatematerial through the first flow passage to the outlet line and tofacilitate flow of the purging airflow through the second flow passageto the outlet line while the valve is in a first state, and the valve isconfigured to substantially block flow of the fluidized particulatematerial through the first flow passage to the outlet line and tofacilitate flow of the purging airflow through the second flow passageto the outlet line while the valve is in a second state.
 10. The portinterface of claim 9, wherein the valve comprises a movable blade havinga first opening and a second opening, wherein the first opening issubstantially aligned with the first flow passage and the second openingis substantially aligned with the second flow passage while the valve isin the first state, and the first opening is substantially aligned withthe second flow passage and a solid portion of the movable blade issubstantially aligned with the first flow passage while the valve is inthe second state.
 11. The port interface of claim 10, wherein the valvecomprises an actuator configured to drive the movable blade.
 12. Theport interface of claim 9, wherein an inlet of the first flow passage iscoupled to the outlet port of the header.
 13. The port interface ofclaim 9, comprising a combiner disposed downstream from the valve andconfigured to combine the fluidized particulate material and the purgingairflow.
 14. The port interface of claim 9, wherein the second flowpassage is fluidly coupled to an inlet passage of the header.
 15. Apneumatic distribution system, comprising: a header comprising an inletpassage and a plurality of outlet ports, wherein the inlet passage isconfigured to receive fluidized particulate material, and each outletport of the plurality of outlet ports is configured to provide thefluidized particulate material to a respective outlet line; and at leastone port interface, comprising: a first flow passage having an inletcoupled to a respective outlet port of the plurality of outlet ports,wherein the first flow passage is configured to receive the fluidizedparticulate material from the respective outlet port and to output thefluidized particulate material to the respective outlet line; a secondflow passage configured to receive a purging airflow and to output thepurging airflow to the respective outlet line; and a knife valve havinga blade, wherein the blade has a first opening and a second opening;wherein the blade is configured to move between a first position inwhich the first opening is substantially aligned with the first flowpassage and the second opening is substantially aligned with the secondflow passage, and a second position in which the first opening issubstantially aligned with the second flow passage and a solid portionof the blade is substantially aligned with the first flow passage. 16.The pneumatic distribution system of claim 15, wherein the at least oneport interface comprises a plurality of port interfaces.
 17. Thepneumatic distribution system of claim 15, wherein the second flowpassage of the at least one port interface is fluidly coupled to theinlet passage of the header.
 18. The pneumatic distribution system ofclaim 15, wherein the knife valve of the at least one port interfacecomprises an actuator configured to drive the blade between the firstand second positions.
 19. The pneumatic distribution system of claim 15,wherein the at least one port interface comprises a combiner disposeddownstream from the knife valve and configured to combine the fluidizedparticulate material and the purging airflow.
 20. The pneumaticdistribution system of claim 19, wherein the combiner comprises a firstinlet fluidly coupled to the first flow passage, a second inlet fluidlycoupled to the second flow passage, and an outlet configured to fluidlycouple to the respective outlet line.